/* GIMPLE lowering pass. Converts High GIMPLE into Low GIMPLE.
- Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009
+ Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
Free Software Foundation, Inc.
This file is part of GCC.
#include "coretypes.h"
#include "tm.h"
#include "tree.h"
-#include "rtl.h"
-#include "varray.h"
#include "gimple.h"
#include "tree-iterator.h"
#include "tree-inline.h"
-#include "diagnostic.h"
-#include "langhooks.h"
-#include "langhooks-def.h"
#include "tree-flow.h"
-#include "timevar.h"
-#include "except.h"
-#include "hashtab.h"
#include "flags.h"
#include "function.h"
-#include "expr.h"
-#include "toplev.h"
+#include "diagnostic-core.h"
#include "tree-pass.h"
/* The differences between High GIMPLE and Low GIMPLE are the
of the function. */
VEC(return_statements_t,heap) *return_statements;
+ /* True if the current statement cannot fall through. */
+ bool cannot_fallthru;
+
/* True if the function calls __builtin_setjmp. */
bool calls_builtin_setjmp;
};
x = gimple_build_label (t.label);
gsi_insert_after (&i, x, GSI_CONTINUE_LINKING);
-
- /* Remove the line number from the representative return statement.
- It now fills in for many such returns. Failure to remove this
- will result in incorrect results for coverage analysis. */
- gimple_set_location (t.stmt, UNKNOWN_LOCATION);
gsi_insert_after (&i, t.stmt, GSI_CONTINUE_LINKING);
}
and insert. */
disp_var = create_tmp_var (ptr_type_node, "setjmpvar");
arg = build_addr (disp_label, current_function_decl);
- t = implicit_built_in_decls[BUILT_IN_SETJMP_DISPATCHER];
+ t = builtin_decl_implicit (BUILT_IN_SETJMP_DISPATCHER);
x = gimple_build_call (t, 1, arg);
gimple_call_set_lhs (x, disp_var);
return 0;
}
-struct gimple_opt_pass pass_lower_cf =
+struct gimple_opt_pass pass_lower_cf =
{
{
GIMPLE_PASS,
PROP_gimple_lcf, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
- TODO_dump_func /* todo_flags_finish */
+ 0 /* todo_flags_finish */
}
};
+
/* Verify if the type of the argument matches that of the function
declaration. If we cannot verify this or there is a mismatch,
return false. */
-bool
-gimple_check_call_args (gimple stmt)
+static bool
+gimple_check_call_args (gimple stmt, tree fndecl)
{
- tree fndecl, parms, p;
+ tree parms, p;
unsigned int i, nargs;
+ /* Calls to internal functions always match their signature. */
+ if (gimple_call_internal_p (stmt))
+ return true;
+
nargs = gimple_call_num_args (stmt);
/* Get argument types for verification. */
- fndecl = gimple_call_fndecl (stmt);
- parms = NULL_TREE;
if (fndecl)
parms = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
- else if (POINTER_TYPE_P (TREE_TYPE (gimple_call_fn (stmt))))
- parms = TYPE_ARG_TYPES (TREE_TYPE (TREE_TYPE (gimple_call_fn (stmt))));
+ else
+ parms = TYPE_ARG_TYPES (gimple_call_fntype (stmt));
/* Verify if the type of the argument matches that of the function
declaration. If we cannot verify this or there is a mismatch,
{
for (i = 0, p = DECL_ARGUMENTS (fndecl);
i < nargs;
- i++, p = TREE_CHAIN (p))
+ i++, p = DECL_CHAIN (p))
{
/* We cannot distinguish a varargs function from the case
of excess parameters, still deferring the inlining decision
return true;
}
+/* Verify if the type of the argument and lhs of CALL_STMT matches
+ that of the function declaration CALLEE.
+ If we cannot verify this or there is a mismatch, return false. */
+
+bool
+gimple_check_call_matching_types (gimple call_stmt, tree callee)
+{
+ tree lhs;
+
+ if ((DECL_RESULT (callee)
+ && !DECL_BY_REFERENCE (DECL_RESULT (callee))
+ && (lhs = gimple_call_lhs (call_stmt)) != NULL_TREE
+ && !useless_type_conversion_p (TREE_TYPE (DECL_RESULT (callee)),
+ TREE_TYPE (lhs))
+ && !fold_convertible_p (TREE_TYPE (DECL_RESULT (callee)), lhs))
+ || !gimple_check_call_args (call_stmt, callee))
+ return false;
+ return true;
+}
/* Lower sequence SEQ. Unlike gimplification the statements are not relowered
when they are changed -- if this has to be done, the lowering routine must
lower_omp_directive (gimple_stmt_iterator *gsi, struct lower_data *data)
{
gimple stmt;
-
+
stmt = gsi_stmt (*gsi);
lower_sequence (gimple_omp_body (stmt), data);
}
-/* Lower statement GSI. DATA is passed through the recursion. */
+/* Lower statement GSI. DATA is passed through the recursion. We try to
+ track the fallthruness of statements and get rid of unreachable return
+ statements in order to prevent the EH lowering pass from adding useless
+ edges that can cause bogus warnings to be issued later; this guess need
+ not be 100% accurate, simply be conservative and reset cannot_fallthru
+ to false if we don't know. */
static void
lower_stmt (gimple_stmt_iterator *gsi, struct lower_data *data)
{
case GIMPLE_BIND:
lower_gimple_bind (gsi, data);
+ /* Propagate fallthruness. */
return;
case GIMPLE_COND:
- /* The gimplifier has already lowered this into gotos. */
- break;
+ case GIMPLE_GOTO:
+ case GIMPLE_SWITCH:
+ data->cannot_fallthru = true;
+ gsi_next (gsi);
+ return;
case GIMPLE_RETURN:
- lower_gimple_return (gsi, data);
+ if (data->cannot_fallthru)
+ {
+ gsi_remove (gsi, false);
+ /* Propagate fallthruness. */
+ }
+ else
+ {
+ lower_gimple_return (gsi, data);
+ data->cannot_fallthru = true;
+ }
return;
case GIMPLE_TRY:
- lower_sequence (gimple_try_eval (stmt), data);
- lower_sequence (gimple_try_cleanup (stmt), data);
+ {
+ bool try_cannot_fallthru;
+ lower_sequence (gimple_try_eval (stmt), data);
+ try_cannot_fallthru = data->cannot_fallthru;
+ data->cannot_fallthru = false;
+ lower_sequence (gimple_try_cleanup (stmt), data);
+ /* See gimple_stmt_may_fallthru for the rationale. */
+ if (gimple_try_kind (stmt) == GIMPLE_TRY_FINALLY)
+ {
+ data->cannot_fallthru |= try_cannot_fallthru;
+ gsi_next (gsi);
+ return;
+ }
+ }
break;
case GIMPLE_CATCH:
+ data->cannot_fallthru = false;
lower_sequence (gimple_catch_handler (stmt), data);
break;
case GIMPLE_EH_FILTER:
+ data->cannot_fallthru = false;
lower_sequence (gimple_eh_filter_failure (stmt), data);
break;
+ case GIMPLE_EH_ELSE:
+ lower_sequence (gimple_eh_else_n_body (stmt), data);
+ lower_sequence (gimple_eh_else_e_body (stmt), data);
+ break;
+
case GIMPLE_NOP:
case GIMPLE_ASM:
case GIMPLE_ASSIGN:
- case GIMPLE_GOTO:
case GIMPLE_PREDICT:
case GIMPLE_LABEL:
- case GIMPLE_SWITCH:
case GIMPLE_EH_MUST_NOT_THROW:
case GIMPLE_OMP_FOR:
case GIMPLE_OMP_SECTIONS:
&& DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
&& DECL_FUNCTION_CODE (decl) == BUILT_IN_SETJMP)
{
- data->calls_builtin_setjmp = true;
lower_builtin_setjmp (gsi);
+ data->cannot_fallthru = false;
+ data->calls_builtin_setjmp = true;
return;
}
- /* After a noreturn call, remove a subsequent GOTO or RETURN that might
- have been mechanically added; this will prevent the EH lowering pass
- from adding useless edges and thus complicating the initial CFG. */
if (decl && (flags_from_decl_or_type (decl) & ECF_NORETURN))
{
+ data->cannot_fallthru = true;
gsi_next (gsi);
- if (!gsi_end_p (*gsi)
- && (gimple_code (gsi_stmt (*gsi)) == GIMPLE_GOTO
- || gimple_code (gsi_stmt (*gsi)) == GIMPLE_RETURN))
- gsi_remove (gsi, false);
return;
}
}
case GIMPLE_OMP_PARALLEL:
case GIMPLE_OMP_TASK:
+ data->cannot_fallthru = false;
lower_omp_directive (gsi, data);
+ data->cannot_fallthru = false;
return;
+ case GIMPLE_TRANSACTION:
+ lower_sequence (gimple_transaction_body (stmt), data);
+ break;
+
default:
gcc_unreachable ();
}
+ data->cannot_fallthru = false;
gsi_next (gsi);
}
{
case GOTO_EXPR:
case RETURN_EXPR:
- /* Easy cases. If the last statement of the block implies
+ /* Easy cases. If the last statement of the block implies
control transfer, then we can't fall through. */
return false;
case CALL_EXPR:
/* Functions that do not return do not fall through. */
return (call_expr_flags (stmt) & ECF_NORETURN) == 0;
-
+
case CLEANUP_POINT_EXPR:
return block_may_fallthru (TREE_OPERAND (stmt, 0));
case GIMPLE_GOTO:
case GIMPLE_RETURN:
case GIMPLE_RESX:
- /* Easy cases. If the last statement of the seq implies
+ /* Easy cases. If the last statement of the seq implies
control transfer, then we can't fall through. */
return false;
case GIMPLE_SWITCH:
- /* Switch has already been lowered and represents a
- branch to a selected label and hence can not fall through. */
- return true;
+ /* Switch has already been lowered and represents a branch
+ to a selected label and hence can't fall through. */
+ return false;
case GIMPLE_COND:
/* GIMPLE_COND's are already lowered into a two-way branch. They
return (gimple_seq_may_fallthru (gimple_try_eval (stmt))
&& gimple_seq_may_fallthru (gimple_try_cleanup (stmt)));
- case GIMPLE_ASSIGN:
- return true;
+ case GIMPLE_EH_ELSE:
+ return (gimple_seq_may_fallthru (gimple_eh_else_n_body (stmt))
+ || gimple_seq_may_fallthru (gimple_eh_else_e_body (stmt)));
case GIMPLE_CALL:
/* Functions that do not return do not fall through. */
return (gimple_call_flags (stmt) & ECF_NORETURN) == 0;
-
+
default:
return true;
}
tmp_rs = *VEC_index (return_statements_t, data->return_statements, i);
if (gimple_return_retval (stmt) == gimple_return_retval (tmp_rs.stmt))
- goto found;
+ {
+ /* Remove the line number from the representative return statement.
+ It now fills in for many such returns. Failure to remove this
+ will result in incorrect results for coverage analysis. */
+ gimple_set_location (tmp_rs.stmt, UNKNOWN_LOCATION);
+
+ goto found;
+ }
}
/* Not found. Create a new label and record the return statement. */
/* Generate a goto statement and remove the return statement. */
found:
+ /* When not optimizing, make sure user returns are preserved. */
+ if (!optimize && gimple_has_location (stmt))
+ DECL_ARTIFICIAL (tmp_rs.label) = 0;
t = gimple_build_goto (tmp_rs.label);
gimple_set_location (t, gimple_location (stmt));
gimple_set_block (t, gimple_block (stmt));
gsi_remove (gsi, false);
}
-/* Lower a __builtin_setjmp TSI.
+/* Lower a __builtin_setjmp GSI.
__builtin_setjmp is passed a pointer to an array of five words (not
all will be used on all machines). It operates similarly to the C
/* Build '__builtin_setjmp_setup (BUF, NEXT_LABEL)' and insert. */
arg = build_addr (next_label, current_function_decl);
- t = implicit_built_in_decls[BUILT_IN_SETJMP_SETUP];
+ t = builtin_decl_implicit (BUILT_IN_SETJMP_SETUP);
g = gimple_build_call (t, 2, gimple_call_arg (stmt, 0), arg);
gimple_set_location (g, loc);
gimple_set_block (g, gimple_block (stmt));
/* Build 'DEST = 0' and insert. */
if (dest)
{
- g = gimple_build_assign (dest, fold_convert_loc (loc, TREE_TYPE (dest),
- integer_zero_node));
+ g = gimple_build_assign (dest, build_zero_cst (TREE_TYPE (dest)));
gimple_set_location (g, loc);
gimple_set_block (g, gimple_block (stmt));
gsi_insert_before (gsi, g, GSI_SAME_STMT);
/* Build '__builtin_setjmp_receiver (NEXT_LABEL)' and insert. */
arg = build_addr (next_label, current_function_decl);
- t = implicit_built_in_decls[BUILT_IN_SETJMP_RECEIVER];
+ t = builtin_decl_implicit (BUILT_IN_SETJMP_RECEIVER);
g = gimple_build_call (t, 1, arg);
gimple_set_location (g, loc);
gimple_set_block (g, gimple_block (stmt));
if (fn != current_function_decl)
push_cfun (DECL_STRUCT_FUNCTION (fn));
- for (; vars; vars = TREE_CHAIN (vars))
+ for (; vars; vars = DECL_CHAIN (vars))
{
tree var = vars;
continue;
/* Record the variable. */
- cfun->local_decls = tree_cons (NULL_TREE, var,
- cfun->local_decls);
+ add_local_decl (cfun, var);
+ if (gimple_referenced_vars (cfun))
+ add_referenced_var (var);
}
if (fn != current_function_decl)